Modularization Of A Hydrocarbon Processing Plant

ABSTRACT

A hydrocarbon processing plant, such an LNG plant, is disclosed. A piperack structure has a major axis parallel to the major axis of the train with which it is associated. A first multipurpose module, substantially pre-assembled prior to being transported to an operating location, has a major axis that is either parallel or perpendicular to the major axis of the piperack. The first multipurpose module contains: process components that perform a function related to hydrocarbon processing or handling; piping systems that connect the process components directly to a second module that is adjacent the first multipurpose module, and wherein at least part of the piping systems are aligned with the major axis of the piperack structure; and at least one heat exchanger located in the first multipurpose module and operationally connected to process components in the hydrocarbon processing plant.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the priority benefit of U.S. Patent Application 62/237,838 filed Oct. 6, 2015 entitled MODULARLIZATION OF A HYDROCARBON PROCESSING PLANT, the entirety of which is incorporated by reference herein.

BACKGROUND

Field of Disclosure

The disclosure relates generally to the field of hydrocarbon processing plants. More specifically, the disclosure relates to the efficient design, construction and operation of hydrocarbon processing plants, such as LNG processing plants.

Description of Related Art

This section is intended to introduce various aspects of the art, which may be associated with the present disclosure. This discussion is intended to provide a framework to facilitate a better understanding of particular aspects of the present disclosure. Accordingly, it should be understood that this section should be read in this light, and not necessarily as admissions of prior art.

In a time when competition for LNG production contracts is increasing, there is a tremendous need to enhance the profitability of future LNG projects. To do so, LNG producers may identify and optimize the key cost drivers and efficiencies applicable to each project.

Rendering projects economical in locations with high costs and low on-site labor productivity may require minimizing the scope and extent of site labor required to construct and commission the LNG plant. Modularization techniques are being employed to tackle this challenge by shifting scope from being built on-site to being built in specialized fabrication yards. However, for large scale LNG projects the modularization of construction scope can still result in significant site integration costs. Accordingly, there is a recognized need in the plant construction industry to remove additional work scope from the plant site compared to other modularization methods currently deployed by industry.

FIGS. 1 and 2 depict a known layout of an LNG producing facility, which may be termed an LNG train 10. The LNG train 10 includes multiple processing units disposed along a central piperack 12. The processing units are connected to each other and to any functional units within the piperack via multiple pipes and conduits that direct utility streams, feed gas 14 and resulting products and side-products as desired. In the example shown in FIG. 1, the LNG train 10 includes an acid gas removal (AGR) unit 16 that removes CO₂ and H₂S molecules from the feed gas 14 down to the very low levels required to prevent freezing in the downstream refrigeration and liquefaction units. A dehydration unit 18 removes water molecules from the feed gas down to the very low levels required to prevent freezing in the downstream refrigeration and liquefaction units. A Heavy Hydrocarbon Capture (HHC) or heavy hydrocarbon removal unit 20 removes C₆ ⁺ molecules from the feed gas below levels necessary to prevent freezing in the downstream refrigeration and liquefaction units. The dehydration unit 18 and the HHC unit 20 may be separate, or as shown in FIG. 1, may be combined into a single module. Other processing units, such as a cryogenic heat exchanger and end-flash gas equipment 22, refrigeration compressors 24 and 26, and a C₃ chiller unit 28, are also included. Refrigeration and liquefaction of the feed gas are achieved using any of the various known refrigeration circuits. As an example, mechanical refrigeration coolers 30, 32 are included in or on the piperack 12 and the resulting extracted enthalpy is rejected using ambient cooled heat exchangers, such as air fin coolers 34 (FIG. 2) arranged in, or preferably on, the piperack 12. Mechanical power is delivered by one or more drivers (not shown) to the refrigeration compressors 24, 26. The multiple drivers may be gas-fired turbines, electric motors, or the like. A refrigerant desuperheater and subcooler unit 36 and a refrigerant condenser unit 38 are used to desuperheat, condense, and subcool spent refrigerant (such as propane) according to known principles, to reject enthalpy using ambient cooled heat exchangers, such as air fin coolers. The LNG train 10 may be further modularized by dividing the piperack 12 into modules 12 a, 12 b, 12 c, 12 d, and 12 e. Each of the processing units and the piperack modules may be pre-assembled at a fabrication yard or other off-site manufacturing location, transported to the operating site of the LNG train, and connected together to construct the completed LNG train.

The LNG train 10 shown in FIG. 1 represents known attempts to modularize gas processing plant design, and is characterized by installing process units (such as the AGR unit, dehydration unit and/or the HHC unit) along the central piperack 12, and piping connections between separate units are routed through the central piperack 12. However, this modularization strategy results in a significant number of piping connections at the interfaces between the process units and the piperack modules. Connecting the piping connections onsite is a labor-intensive activity. Furthermore, every line 33 connecting two process modules, such as the AGR unit 16 and the dehydration unit 18, must pass through the piperack to do so, and there will be a minimum of two site connections at interfaces with each central piperack segment installed individually at site which is traversed by the line.

Additionally, in ambient air-cooled LNG train designs the air-cooled heat exchangers 34 are generally installed in a bank or banks on top of the central piperack structure. The size and number of these heat exchangers may establish the length and width of the central piperack 12 and, as a result, the overall footprint of the LNG train. This layout results in a significant number of labor-intensive large bore piping connections at the interfaces between air cooler piperack modules and pipe segments running through the piperack modules, and these connections usually are finished at an operating site rather than a manufacturing site.

Another attempt to modularize the design of an LNG train uses small capacity LNG trains (˜2 MTA) and uses a single natural gas treatment module that performs the functions of the AGR unit, the dehydration unit, and the HHC unit. However, if a higher capacity of LNG is required to be processed, multiple identical modular trains must be used, which results in the duplication of module interconnections and associated work scope at the LNG site. Therefore, a need exists for a modularized design for a high-capacity hydrocarbons processing plant, such as an LNG train, in which the amount of work to assemble modular parts thereof at an operating site is minimized.

SUMMARY

In an aspect, a hydrocarbon processing plant is disclosed. A piperack structure has a major axis parallel to the major axis of the train with which it is associated. A first multipurpose module, substantially pre-assembled prior to being transported to an operating site, has a major axis that is parallel to the major axis of the piperack. The first multipurpose module contains: process components that perform a function related to hydrocarbon processing or handling; piping systems that connect the process components directly to a second, where the second multipurpose module is adjacent the first multipurpose module, and wherein at least part of the piping systems are aligned with the major axis of the piperack structure; and at least one heat exchanger located in the first multipurpose module and operationally connected to process components in the hydrocarbon processing plant.

The present disclosure also provides a method of hydrocarbon processing plant. A piperack structure has a major axis parallel to the major axis of the train with which it is associated. A first multipurpose module, substantially pre-assembled prior to being transported to an operating site, has a major axis that is perpendicular or substantially perpendicular to the major axis of the piperack. The first multipurpose module contains: process components that perform a function related to hydrocarbon processing or handling; piping systems that connect the process components directly to a second module, where the second module is adjacent the first multipurpose module, and wherein at least part of the piping systems are aligned with the major axis of the piperack structure; and a plurality of heat exchangers located in the first multipurpose module and operationally connected to process components located in the hydrocarbon processing plant. The plurality of heat exchangers are aligned with the major axis of the first multipurpose module.

The present disclosure further provides a method of constructing a hydrocarbon processing plant. A train is provided at an operating site. The train has a major axis. A piperack structure is provided at the operating site. The piperack structure has a major axis that is parallel to the major axis of the train. A heat exchanger bank is provided that runs along the major axis of the train. A first multipurpose module is substantially pre-assembled at a manufacturing site that is separate from the operating site. The first multipurpose module includes: process components that perform a function related to hydrocarbon processing or handling; piping systems; and a plurality of heat exchangers operationally connected to process components in the train, wherein the plurality of heat exchangers are aligned with the major axis of the first multipurpose module. The first multipurpose module is transported to the operating site. The first multipurpose module is operationally connected, at the operating site, to the train such that (a) the major axis of the first multipurpose module is either parallel or substantially perpendicular to the major axis of the piperack, (b) the piping systems connect the process components directly to a second module that is adjacent the first multipurpose module, and (c) at least part of the piping systems are aligned with the major axis of the piperack structure.

The foregoing has broadly outlined the features of the present disclosure so that the detailed description that follows may be better understood. Additional features will also be described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects and advantages of the disclosure will become apparent from the following description, appending claims and the accompanying drawings, which are briefly described below.

FIG. 1 is a schematic diagram of an LNG train according to known principles.

FIG. 2 is a top plan view of an LNG train according to known principles.

FIG. 3 is a schematic diagram of an LNG train.

FIG. 4 is a schematic diagram of an LNG train.

FIG. 5 is a top plan view of an LNG train.

FIG. 6 is a top plan view of an LNG train.

FIG. 7 is a top plan view of an LNG train.

FIG. 8 is a flowchart of a method according to aspects of the disclosure.

It should be noted that the figures are merely examples and no limitations on the scope of the present disclosure are intended thereby. Further, the figures are generally not drawn to scale, but are drafted for purposes of convenience and clarity in illustrating various aspects of the disclosure.

DETAILED DESCRIPTION

For the purpose of promoting an understanding of the principles of the disclosure, reference will now be made to the features illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the disclosure is thereby intended. Any alterations and further modifications, and any further applications of the principles of the disclosure as described herein are contemplated as would normally occur to one skilled in the art to which the disclosure relates. It will be apparent to those skilled in the relevant art that some features that are not relevant to the present disclosure may not be shown in the drawings for the sake of clarity.

At the outset, for ease of reference, certain terms used in this application and their meanings as used in this context are set forth. To the extent a term used herein is not defined below, it should be given the broadest definition persons in the pertinent art have given that term as reflected in at least one printed publication or issued patent. Further, the present techniques are not limited by the usage of the terms shown below, as all equivalents, synonyms, new developments, and terms or techniques that serve the same or a similar purpose are considered to be within the scope of the present claims.

As one of ordinary skill would appreciate, different persons may refer to the same feature or component by different names. This document does not intend to distinguish between components or features that differ in name only. The figures are not necessarily to scale. Certain features and components herein may be shown exaggerated in scale or in schematic form and some details of conventional elements may not be shown in the interest of clarity and conciseness. When referring to the Figures described herein, the same reference numerals may be referenced in multiple figures for the sake of simplicity. In the following description and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus, should be interpreted to mean “including, but not limited to.”

The articles “the,” “a” and “an” are not necessarily limited to mean only one, but rather are inclusive and open ended so as to include, optionally, multiple such elements.

As utilized herein, the terms “approximately,” “about,” “substantially,” and similar terms are intended to have a broad meaning in harmony with the common and accepted usage by those of ordinary skill in the art to which the subject matter of this disclosure pertains. It should be understood by those of skill in the art who review this disclosure that these terms are intended to allow a description of certain features described and claimed without restricting the scope of these features to the precise numeral ranges provided. Accordingly, these terms should be interpreted as indicating that insubstantial or inconsequential modifications or alterations of the subject matter described and are considered to be within the scope of the disclosure. Nevertheless, an element is “substantially perpendicular” to a reference element when the element is oriented at an angle of between 80 degrees and 100 degrees to the reference element.

The term “acid gas” and “sour gas” refers to any gas that dissolves in water to produce an acidic solution. Non-limiting examples of acid gases include hydrogen sulfide (H₂S), carbon dioxide (CO₂), or sulfur dioxide (SO₂), or mixtures thereof.

The term “heat exchanger” refers to a device designed to efficiently transfer or “exchange” heat from one matter to another. Exemplary heat exchanger types include a co-current or counter-current heat exchanger, an indirect heat exchanger (e.g. spiral wound heat exchanger, plate-fin heat exchanger such as a brazed aluminum plate fin type, shell-and-tube heat exchanger, etc.), direct contact heat exchanger, or some combination of these, and so on.

The “major axis” of an element refers to a line of symmetry parallel to the predominant linear dimension of the element. In other words, an element is longest in a direction of its major axis than along any other axis perpendicular or substantially perpendicular thereto.

The term “piperack” refers to a structural system that supports pipes, conduits tubes, and the like.

Although the phrases “gas stream,” “vapor stream,” and “liquid stream,” refer to situations where a gas, vapor, and liquid is mainly present in the stream, respectively, there may be other phases also present within the stream. For example, a gas may also be present in a “liquid stream.” In some instances, the terms “gas stream” and “vapor stream” may be used interchangeably.

The disclosure relates to a system and method for the standardized design and construction of a hydrocarbon processing plant, such as an LNG train. In an aspect, a significant number of connections between modules and/or processing units may be eliminated by integrating process equipment and piperack components in multipurpose modules that are connected to other distinct abutting modules. Additionally, ambient cooled heat exchangers, such as air fin coolers, can be located in the multipurpose modules. This is in contrast to the traditional LNG train design where (1) all process units and modules are arranged around a central piperack and (2) ambient cooled heat exchangers rejecting heat from the process units are located in or on the central piperack.

FIGS. 3-7 of the disclosure display various aspects of the system and method in comparison with known LNG plant layouts. FIG. 3 depicts a hydrocarbon processing plant, and specifically depicts an LNG train 300. The LNG train may have a major axis 302. The LNG train 300 may include multiple processing units disposed along a central piperack 312. The central piperack 312 may have a major axis 304. In an aspect, the major axis 302 of the LNG train 300 and the major axis 304 of the central piperack 312 are parallel to each other. In a further aspect, the major axis 302 and the major axis 304 overlay each other, or in other words, are co-incident. The central piperack 312 may be divided into multiple piperack modules. The processing units may be connected other processing units, to adjacent piperack modules, and/or to any functional units within or co-located with the central piperack 312, via multiple pipes and conduits that direct a feed gas stream 314 and resulting products and side-products as desired. In an aspect shown in FIG. 3, the processing units may include a dehydration unit 318, which may be included to remove water molecules from the feed gas down to the very low levels required to prevent freezing in the downstream refrigeration and liquefaction units. Another processing unit may be a heavy hydrocarbon capture (HHC) or heavy hydrocarbon removal unit 320, which may be included to remove C₆ ⁺ molecules from the feed gas below levels necessary to prevent freezing in the downstream refrigeration and liquefaction units. The dehydration unit 318 and the HHC unit 320 may be separate, or as shown in FIG. 3, may be combined into a single module. Other processing units, such as a cryogenic heat exchanger and end-flash gas equipment 322, refrigeration compressors 324 and 326, and a C₃ chiller unit 328, may also be included. Refrigeration and liquefaction of the feed gas are achieved using any of the various known refrigeration circuits. As an example, mechanical refrigeration coolers 330, 332 are included in or on the piperack 312 and the resulting extracted enthalpy is rejected using ambient cooled heat exchangers, such as air fin coolers arranged in, or preferably on, the piperack 312. Mechanical power is delivered by one or more drivers (not shown) to the refrigeration compressors 324, 326. The multiple drivers may be gas-fired turbines, electric motors, or the like. A refrigerant desuperheater and subcooler unit 336 and a refrigerant condenser unit (not shown) are used to desuperheat, condense, and subcool spent refrigerant (such as propane) according to known principles, to reject enthalpy using ambient cooled heat exchangers, such as air fin coolers. Each of the processing units and the piperack modules may be pre-assembled at manufacturing site such as a fabrication yard or other off-site location, transported to an assembly site such as the expected operating site or location of the LNG train, and connected together to construct the completed LNG train.

The LNG train 300 may also include acid gas removal (AGR) equipment or components that remove CO₂ and H₂S molecules from the feed gas 314 down to the very low levels required to prevent freezing in the downstream refrigeration and liquefaction units. As shown in FIG. 3, the AGR equipment or components are modularized to form a multipurpose AGR module 316. The AGR module is termed ‘multipurpose’ because it includes process components that perform the AGR function, piping systems that connect the AGR components to other multipurpose modules or to the central piperack, and at least one heat exchanger (preferably an ambient cooled heat exchanger) operationally connected to the AGR components or to other processing components elsewhere in the LNG train 300. Other processing units may also be defined as multipurpose processing units as desired. The multipurpose AGR module 316 is located at the front end of the LNG train 300, and piping connections from the remainder of the central piperack 312 to the multipurpose AGR module 316 and/or to other processing units may be routed through the multipurpose AGR module 316. All ambient cooled heat exchangers used by the AGR process, such as a lean amine cooler (not shown) and/or a regenerator overhead cooler (not shown) are located in or on the multipurpose AGR module 316. This configuration eliminates multiple connections between the multipurpose AGR module 316 and the central piperack 312 that were required in the conventional layout configuration described and shown in FIGS. 1 and 2. For example, installation site labor cost savings are realized by eliminating four or more large bore connections (greater than 12 inches or about 0.3 meters) and ten or more small bore connections (less than 12 inches or about 0.3 meters). As another example, the AGR module may comprise an amine solvent unit used for the removal of acid gas from the natural gas stream. As a further example, amine-based AGR may use two large columns: an amine absorber and an amine regenerator. These two columns may be included in the multipurpose AGR module 316. Alternatively, these two columns may be erected and connected to the multipurpose AGR module 316 at the operating site.

Another aspect is shown in the LNG train 400 of FIG. 4. The LNG train may have a major axis 402. The LNG train 400 may include multiple processing units disposed along a central piperack 412. The central piperack 412 may have a major axis 404. In an aspect, the major axis 402 of the LNG train 400 and the major axis 404 of the central piperack 412 are parallel to each other. In a further aspect, the major axis 402 and the major axis 404 overlay each other or are co-incident with each other. The central piperack 412 may be divided into multiple piperack modules. The processing units may be connected to each other and to any functional units within or co-located with the central piperack 412 via multiple pipes and conduits that direct a feed gas stream and resulting products and side-products as desired. In an aspect shown in FIG. 4, the processing units may include an AGR processing module 416, which may be an multipurpose AGR processing module as previously described. The AGR processing module 416 is disposed along the central piperack 412 but separate from the major axis 404 of the central piperack 412. Other processing units or modules may be included as previously described, such as: a cryogenic heat exchanger and end-flash gas equipment 422; refrigeration compressors 424 and 426; a C₃ chiller unit 428; mechanical refrigeration coolers 430, 432; a refrigerant desuperheater and subcooler unit 436; and a refrigerant condenser unit 438.

Equipment that performs the dehydration process may be modularized and integrated with a piperack section or module to form a multipurpose dehydration/HHC module 418. The multipurpose dehydration/HHC module 418 may be located at the appropriate location for LNG processing, which as shown in FIG. 4 is toward the front end 406 of the LNG train 400 and downstream of the multipurpose AGR module 416. For the purpose of removing heavy hydrocarbons from the natural gas stream, the multipurpose dehydration/HHC module 418 may include one or more of a scrub column, a molecular sieve adsorption bed, and a Joule-Thompson assembly. The multipurpose dehydration/HHC module 418 may include a molecular sieve adsorption bed for dehydration, which may be located in a sequence that is parallel to the central piperack. In another aspect, the molecular sieve adsorption bed associated with dehydration is located in the same multipurpose module with the molecular sieve adsorption bed associated with extraction of heavy hydrocarbons (i.e., C₆ ⁺ components) from a natural gas stream, and wherein both molecular sieve adsorption beds are located in a sequence that is parallel to the piperack assembly.

Piping connections from the piperack 412 and the multipurpose AGR module 416 connecting to other downstream processing units or piperack modules in the LNG train are routed through the multipurpose dehydration/HHC module 418. All or substantially all ambient cooled heat exchangers used in the dehydration and HHC processes, such as a regeneration gas cooler, are located on or in the multipurpose dehydration/HHC module. This solution eliminates multiple connections between the multipurpose dehydration/HHC module 418 and the piperack 412 that were required in known LNG layout configurations as previously described.

FIG. 5 shows other aspects of the disclosed invention. LNG train 500 includes a central piperack 512 that has a major axis 504 that overlays or is co-incident with the major axis 502 of the LNG train 500. The central piperack 512 comprises piperack modules 512 a, 512 b, 512 c, 512 d, and 512 e. Each of the piperack modules 512 a-e may be manufactured at a manufacturing site and transported to an assembly site, which may be the operating location of the LNG train, to be assembled together. Other processing units of LNG train 500 may include a cryogenic heat exchanger and end-flash gas equipment 522, refrigeration compressors 524 and 526, and a C₃ chiller unit 528, all as previously described herein. The other processing units previously described (i.e., mechanical refrigeration coolers, refrigerant desuperheater and subcooler unit, and refrigerant condenser unit) form part of the LNG train 500 along its major axis 502. A plurality of heat exchanger units 534, which may be termed a heat exchanger bank, are disposed in or on the central piperack 512 along its major axis 504. The heat exchanger units 534 may be ambient heat exchanger units, and may be ambient air fin heat exchanger units. As shown in FIG. 5, the heat exchanger units 534 may be arrayed in two parallel lines 534 a, 534 b.

A multipurpose AGR module 516 is disposed along the major axis 502 of the LNG train 500. The multipurpose AGR module 516 has a major axis 506. In an aspect, the major axis 506 is parallel to, and/or co-incident with, the major axes 502, 504. The multipurpose AGR module 516 includes heat exchanger units 540 that provide some or all of the required cooling for the AGR equipment or components thereon. The heat exchanger units 540 may be ambient heat exchanger units, and may be ambient air fin heat exchanger units. While the heat exchanger units 540 may be disposed along the major axis 506 and therefore are at least parallel to the disposition of the heat exchanger units 534 associated with the central piperack 512, the heat exchanger units may be designed and configured to provide a heat exchange function only for the equipment or components in the multipurpose AGR module 516, and therefore may not be considered to be part of the heat exchanger units 534, which are designed to provide a heat exchange function for other processing units of the LNG train 500.

A multipurpose dehydration/HHC module 518 is also disposed along the major axis 502 of the LNG train 500. The multipurpose dehydration/HHC module 518 has a major axis 508. The multipurpose dehydration/HHC module 518 includes ambient air fin heat exchangers 542 that provide some or all of the required cooling for the dehydration/HHC equipment or components thereon. The heat exchanger units 542 may be ambient heat exchanger units, and may be ambient air fin heat exchanger units. While the heat exchanger units 542 may be disposed along the major axis 508 and therefore are at least parallel to the disposition of the heat exchanger units 534 associated with the central piperack 512, the heat exchanger units 542 may be designed and configured to provide a heat exchange function only for the equipment or components in the multipurpose dehydration/HHC module 518, and therefore may not be considered to be part of the heat exchanger units 534, which are designed to provide a heat exchange function for other processing units of the LNG train 500.

Another aspect is shown in the LNG train 600 of FIG. 6, which is similar to LNG train 500. LNG train 600 includes a multipurpose AGR module 616 and a multipurpose dehydration/HHC module 618 having major axes 606, 608 parallel but not co-incident with the major axis 604 of the central piperack 612. The multipurpose AGR module 616 and/or the multipurpose dehydration/HHC module 618 may be positioned such that rows of heat exchanger units 640, 642 respectively associated therewith are aligned with one of the parallel lines 634 a, 634 b of the heat exchangers 634 associated with the central piperack 612.

Another aspect is shown in the LNG train 700, which is similar to LNG trains 500 and 600. LNG train 700 includes a multipurpose AGR module 716 having a major axis 706, and a multipurpose dehydration/HHC module 718 having a major axis 708. The multipurpose AGR module 716 is positioned so that its major axis 706 is perpendicular or substantially perpendicular to the major axis 704 of the piperack. Rows of heat exchanger units 740 associated therewith are aligned with major axis 706. The multipurpose dehydration/HHC module 718 is positioned so that its major axis 708 is parallel and/or co-incident with the major axis 704 of the central piperack 712. The multipurpose dehydration/HHC module 718 may be positioned such that rows of heat exchanger units 742 associated therewith are aligned with one of the parallel lines 734 a, 734 b of the heat exchangers 734 associated with the central piperack 712.

In another aspect, the function performed by a multipurpose module may include the mechanical refrigeration of the natural gas stream, which may be accomplished in part by rejecting heat to an ambient (i.e., to the environment at the operating site) using one or more air and/or water- cooled heat exchangers. The mechanical refrigeration may be accomplished in part by a refrigerant comprising propane and/or propylene. Alternatively or additionally, the mechanical refrigeration may be accomplished in part by a mixed refrigerant comprising methane, ethane and/or ethylene, propane and/or propylene, and/or butane.

The disclosed aspects discuss one or more multipurpose modules that are assembled at a manufacturing site that is separate from or distant from the operating site of a hydrocarbon processing facility (such as an LNG plant), transported to the operating site, and connected to parts of the hydrocarbon processing facility. As discussed herein, it may not be feasible to assemble all parts or components of a multipurpose module at a manufacturing site. According to disclosed aspects, a multipurpose module may include components built or assembled on or adjacent the multipurpose module but transported to the operating site separate from the multipurpose module. Such components may be considered to be part of the multipurpose module because the components perform part of the function associated with the remaining components on the multipurpose module. Additionally, while the disclosed aspects have been described as being part of an LNG plant, the aspects may be advantageously used in the construction of other hydrocarbon processing plants.

Another aspect uses refrigerant driver and compressor string modules that include the interstage and discharge coolers for refrigerant compressors. The compressor discharge streams are cooled directly by air cooled heat exchangers installed on the top of the compression string module or by a recirculating or once-through water cooling system with heat exchangers installed within the compression modules. This disclosed aspect can be deployed with either electric motor, gas turbine or steam compressor drivers. The benefits of the disclosed aspects include a decrease in the size of the central piperack and the footprint of the LNG train, a decrease in the number of process streams (e.g. compressor discharge streams) requiring site piping connections to the central piperack, and the cost savings associated with these benefits. Additional benefits are realized by schedule and logistics synergies associated with the reconfigured layout and the opportunity to conduct more pre-commissioning of the refrigerant driver and compressor systems in the fabrication yard. In one example, it is estimated that modularizing the compressors as disclosed herein eliminates approximately 20% of the required man-hours for construction of a single LNG train. With LNG processing plants having three or more LNG trains, the savings in construction costs can be significant. Furthermore, locating air fin coolers on top of the compressor modules has the potential of removing two piperack modules and may eliminate as much as 60 large-bore connections that would otherwise be required to be completed at the assembly site. Additionally, approximately 25% of the high reliability welds (i.e., “golden welds”) are eliminated as well. The cost savings associated with the reduced number of connections and welds is anticipated to be significant.

FIG. 8 depicts a method 800 of constructing a hydrocarbon processing plant according to aspects disclosed herein. At step 802 a train is provided at an operating site. The train has a major axis. At step 804 a piperack structure is provided at the operating site. The piperack structure has a major axis that is parallel to the major axis of the train. At step 806 a heat exchanger bank is provided that runs along the major axis of the train. At step 808 a first multipurpose module is substantially pre-assembled at a manufacturing site that is separate from the operating site. The first multipurpose module includes: process components that perform a function related to hydrocarbon processing or handling; piping systems; and a plurality of heat exchangers operationally connected to process components located therein, wherein the plurality of heat exchangers are aligned with the major axis of the first multipurpose module. At step 810 the first multipurpose module is transported to the operating site. At step 812 the first multipurpose module is operationally connected, at the operating site, to the train such that (a) the major axis of the first multipurpose module is either parallel or substantially perpendicular to the major axis of the piperack, (b) the piping systems connect the process components directly to a second module that is adjacent the first multipurpose module, and (c) at least part of the piping systems are aligned with the major axis of the piperack structure.

The steps depicted in FIG. 8 are provided for illustrative purposes only and a particular step may not be required to perform the inventive methodology. Moreover, FIG. 8 may not illustrate all the steps that may be performed. The claims, and only the claims, define the inventive system and methodology.

Disclosed aspects may be used in hydrocarbon management activities. As used herein, “hydrocarbon management” or “managing hydrocarbons” includes hydrocarbon extraction, hydrocarbon production, hydrocarbon exploration, identifying potential hydrocarbon resources, identifying well locations, determining well injection and/or extraction rates, identifying reservoir connectivity, acquiring, disposing of and/ or abandoning hydrocarbon resources, reviewing prior hydrocarbon management decisions, and any other hydrocarbon-related acts or activities. The term “hydrocarbon management” is also used for the injection or storage of hydrocarbons or CO₂, for example the sequestration of CO₂, such as reservoir evaluation, development planning, and reservoir management. The disclosed methodologies and techniques may be used in extracting hydrocarbons from a subsurface region and/or processing the hydrocarbons. Hydrocarbons and contaminants may be extracted from a reservoir and processed. The hydrocarbons and contaminants may be processed, for example, in the LNG plant or other processing plant as described herein. Other hydrocarbon extraction activities and, more generally, other hydrocarbon management activities, may be performed according to known principles.

It should be understood that the numerous changes, modifications, and alternatives to the preceding disclosure can be made without departing from the scope of the disclosure. The preceding description, therefore, is not meant to limit the scope of the disclosure. Rather, the scope of the disclosure is to be determined only by the appended claims and their equivalents. It is also contemplated that structures and features in the present examples can be altered, rearranged, substituted, deleted, duplicated, combined, or added to each other. 

What is claimed is:
 1. A hydrocarbon processing plant, comprising: a train having a major axis; a piperack structure having a major axis that is parallel to the major axis of the train; a first multipurpose module, configured to be substantially pre-assembled prior to being transported to an operating location, the first multipurpose module having a major axis that is parallel to the major axis of the piperack, the first multipurpose module containing process components that perform a function related to hydrocarbon processing or handling, piping systems that connect the process components directly to a second module, where the second module is adjacent the first multipurpose module, and wherein at least part of the piping systems are aligned with the major axis of the piperack structure, and at least one heat exchanger located in the first multipurpose module and operationally connected to process components in the hydrocarbon processing plant.
 2. The hydrocarbon processing plant of claim 1, wherein the first multipurpose module is part of a liquefied natural gas facility.
 3. The hydrocarbon processing plant of claim 1, wherein the function performed by the process components contained in the first multipurpose module is removal of acid gas from a natural gas stream.
 4. The hydrocarbon processing plant of claim 3, further comprising an amine solvent unit used for the removal of acid gas.
 5. The hydrocarbon processing plant of claim 3, further comprising an amine absorber and at least one amine regenerator column, wherein the amine absorber and the at least one amine regenerator column are configured to be erected and connected to the process components at an installation site of the hydrocarbon processing plant.
 6. The hydrocarbon processing plant of claim 1, wherein the function performed by the process components contained in the first multipurpose module is removal of water from a natural gas stream.
 7. The hydrocarbon processing plant of claim 6, wherein the process components contained in the first multipurpose module comprise molecular sieve adsorption beds arranged in a sequence that is parallel to the major axis of the piperack structure.
 8. The hydrocarbon processing plant of claim 7, wherein the molecular sieve adsorption beds are first molecular sieve adsorption beds, and further comprising second molecular sieve adsorption beds located in the first multipurpose module and associated with extraction of C₆ ³⁰ components from a natural gas stream, wherein the first and second molecular sieve adsorption beds are arranged in a sequence that is parallel to the major axis of the piperack structure.
 9. The hydrocarbon processing plant of claim 1, wherein the function performed by the process components contained in the first multipurpose module is extraction of C₆ ⁺ components from a natural gas stream.
 10. The hydrocarbon processing plant of claim 9, wherein the process components contained in the first multipurpose module comprise one or more of a scrub column and a Joule-Thompson assembly.
 11. The hydrocarbon processing plant of claim 1, wherein the function performed by the process components contained in the first multipurpose module is mechanical refrigeration of a natural gas stream accomplished in part by rejecting heat to an ambient using one or more air and/or water-cooled heat exchangers.
 12. The hydrocarbon processing plant of claim 11, wherein the mechanical refrigeration is accomplished in part by a refrigerant comprising propane and/or propylene, or a mixed refrigerant comprising methane, ethane and/or ethylene, and propane and/or propylene.
 13. The hydrocarbon processing plant of claim 12, wherein the mixed refrigerant further comprises butane.
 14. The hydrocarbon processing plant of claim 1, further comprising operating site-built or operating site-assembled components connected to the first multipurpose module, the operating site-built or operating site-assembled components performing part of the function associated with the process components contained in the first multipurpose module.
 15. The hydrocarbon processing plant of claim 1, wherein the second module is a second multipurpose module configured to be substantially pre-assembled prior to being transported to the operating location, the second multipurpose module containing process components that perform a function related to hydrocarbon processing or handling different from the function performed by the process components of the first multipurpose module.
 16. The hydrocarbon processing plant of claim 1, wherein the second module is a piperack module configured to be substantially pre-assembled prior to being transported to the operating location.
 17. The hydrocarbon processing plant of claim 1, wherein the second module has a major axis that is one of parallel to and perpendicular to the major axis of the piperack structure.
 18. The hydrocarbon processing plant of claim 1, further comprising a heat exchanger bank running along the major axis of the train.
 19. The hydrocarbon processing plant of claim 1, wherein the at least one heat exchanger is aligned with the major axis of the first multipurpose module.
 20. A method of constructing a hydrocarbon processing plant, comprising: providing a train at an operating site, the train having a major axis; providing a piperack structure at the operating site, the piperack structure having a major axis that is parallel to the major axis of the train; providing a heat exchanger bank running along the major axis of the train; substantially pre-assembling a first multipurpose module at a manufacturing site that is separate from the operating site, the first multipurpose module including process components that perform a function related to hydrocarbon processing or handling, piping systems, and a plurality of heat exchangers operationally connected to process components in the train, wherein the plurality of heat exchangers are aligned with a major axis of the first multipurpose module; transporting the first multipurpose module to the operating site; and operationally connecting, at the operating site, the first multipurpose module to the train such that (a) a major axis of the first multipurpose module is either parallel or substantially perpendicular to the major axis of the piperack, (b) the piping systems connect the process components directly to a second module that is adjacent the first multipurpose module, and (c) at least part of the piping systems are aligned with the major axis of the piperack structure.
 21. The method of claim 20, wherein the function performed by the process components contained in the first multipurpose module is removing acid gas from a natural gas stream, and further comprising: erecting and connecting an amine absorber and at least one amine regenerator column to the process components at the operating site.
 22. The method of claim 20, further comprising erecting and connecting, at the operating site, one or more components to the first multipurpose module, the one or more components performing part of the function associated with the process components contained in the first multi-purpose module.
 23. The method of claim 20, wherein the function performed by the process components contained in the first multipurpose module is removing water from a natural gas stream.
 24. The method of claim 23, wherein the process components contained in the first multipurpose module comprise molecular sieve adsorption beds, and further comprising arranging the molecular sieve adsorption beds in a sequence that is parallel to the major axis of the piperack structure.
 25. The method of claim 24, wherein the molecular sieve adsorption beds are first molecular sieve adsorption beds, and further comprising: locating second molecular sieve adsorption beds in the first multipurpose module, the second molecular sieve adsorption beds being associated with extraction of C₆ ⁺ components from a natural gas stream; and arranging the first and second molecular sieve adsorption beds in a sequence that is parallel to the major axis of the piperack structure.
 26. The method of claim 20, wherein the function performed by the process components contained in the first multipurpose module is mechanical refrigeration of a natural gas stream that is accomplished in part by rejecting heat to an ambient using one or more air and/or water-cooled heat exchangers.
 27. The method of claim 26, wherein the mechanical refrigeration is accomplished in part by a refrigerant comprising propane and/or propylene, or a mixed refrigerant comprising methane, ethane and/or ethylene, and propane and/or propylene.
 28. The method of claim 20, wherein the second module is a second multipurpose module containing process components that perform a function related to hydrocarbon processing or handling different from the function performed by the process components of the first multipurpose module, and further comprising: substantially pre-assembling the second multipurpose module prior to being transported to the operating location; and connecting the second multipurpose module to the first multipurpose module at the operating location.
 29. The method of claim 20, wherein the second module is a piperack module that forms part of the piperack structure, the method further comprising: pre-assembling the piperack module prior to being transported to the operating location; and connecting the piperack module to other portions of the piperack structure and to the first multipurpose module at the operating location. 